Standard Non-Pulse Wiper

Fig. 2 Rectangular windshield wiper motor electrical connections:

Operation:
Placing wiper switch in low position grounds motor terminals 1 and 3, Fig. 2, at the wiper switch. Shunt field current flows directly to ground through terminal 3, armature current flows to ground through terminal 1 and the motor runs at low speed. Placing wiper switch in high position grounds terminal 1, but terminal 3 remains open. Armature current flows directly to ground through terminal 1, shunt field current flows to ground through a resistor connected between terminals 1 and 3, and the motor runs at high speed due to the weakened shunt field.

When wiper switch is turned off, and wipers are not in park position, terminal 1 is grounded through the closed motor park switch contacts. Terminals 1 and 3 are connected through the wiper switch, and the motor runs at low speed. When wipers reach their lowest point of travel, a cam on the motor output shaft opens the park switch, and the motor stops.